1. Field of the Invention
In general, the present invention relates to toy bow systems that project toy arrows into flight. More particularly, the present invention relates to the structure of toy projectile launchers and the mechanisms for loading and releasing projectiles.
2. Prior Art Description
Bow and arrow sets that are designed for children's play have existed throughout recorded history. In the modern era, toy bow and arrow sets typically have a plastic molded bow, a string, and safety-tipped arrows. To ensure safety, the functional design of the bow is also commonly altered. In a real bow, the string has a fixed length. The spring force used to launch an arrow comes from the flexing of the arms of the bow. The problem with this design is its failure mode. If a bow is drawn beyond its limit, then the arms or the string of the bow may break. Depending upon where the breakage occurs, the broken string and/or bow may fly toward the person holding the bow as the stored energy is accidentally released.
To reduce the likelihood of this hazard from occurring, many toy bows are manufactured as static structures. An elastic string is used to create the arrow launching force. If such a bow is overdrawn, there is no significant chance of the bow breaking. Rather, the elastic string can break and will most likely move in a direction away from the person drawing the bow. The failure mode of a string breaking is far less dangerous than the failure mode of the bow breaking. However, the failure mode of broken string does present some danger depending upon where the elastic string breaks and how much energy is stored in the elastic string at the time it breaks.
Toy bows that use a static bow and an elastic string are exemplified by U.S. Pat. No. 5,247,920 to Harbin, entitled Toy Bow; and U.S. Pat. No. 7,748,369 to Chee, entitled Launching Apparatus and Assembly. Such elastic string toy bows are also shown in the applicant's earlier patent application Ser. Nos. 12/878,985 and 13/411,951.
Although toy bows with elastic strings are safer than flexible bows with non-elastic strings, a danger still is present. If an elastic string is stretched into a fully drawn state and the elastic string breaks near its mounting point with the bow, then the broken elastic string may whip toward the person pulling on the elastic string. The broken elastic string therefore has the potential to cause physical danger to the child pulling on the string, especially to the eyes of the child.
Many toy bows that have elastic strings use elastic strings that are made from a synthetic polymer, such as silicon, TPR, or some other synthetic rubber. On the toy, such elastic strings are constantly under tension. As such, if the material of the string creeps or degrades, the elastic string will break. In addition to the danger presented, this stops the toy bow from being functional.
Most all plastic degrades in some fashion over time. However, it has been found that one of the fastest ways to degrade the preferred polymers used for the bowstring is to expose the bowstring to UV light. A bowstring that can last for years inside a home may only last for a few days if taken outside and left in sunlight. Damage caused by exposure to sunlight has therefore caused customers to return products and/or consumer's to be dissatisfied.
A need therefore exists for a toy bow and arrow design that inhibits degradation in the elastic string caused by exposure to light. A need also exists for a toy bow and arrow design that eliminates the dangers to a child who may overdraw the bow to a point of string failure. These needs are met by the present invention as described and claimed below.